Attached doc has what you're looking for, as well as contact info in case you seek further info.

"The breeding of this hybrid was masterminded inside the Genetic Department of the Salvadoran Institute for Coffee Research (ISIC) back in 1958 when the institute began a coffee breeding improvement program using hybridization among many varieties, one of these experiments derived into an outstanding hybrid by artificially crossing the Pacas and Red Maragogipe varietals at their fourth generation (F4). After evaluation and selection it was named PACAMARA using the first four letters of each parent.

"With the conception of this intraspecific hybrid researchers sought to combine the desirable characteristics of the Pacas variety such as its shorter size, shorter internodes, higher productivity, adaptability to local conditions and its ability to resist wind, sunlight and droughts with the plant vitality, the lushness of its big leaves and bigger bean size of the Maragogipe, as well as its better cup quality. "

Selection/isolation are the most basic and widespread way we've gathered a lot of the varieties we have come to know and love. Some of the varieties arise from spontaneous mutations, others arise from wild cross-pollination, some are naturally selected because particular plants adapted to adverse conditions, and some are the result of breeding programs. Breeding programs involving cross-pollination tend to be in the hands of institutes like CATIE rather than at the farm level.

A couple of quick examples:

Caturra was a bourbon mutant gathered in Brazil back in the '30's

Maragogype is another mutant discovered in Brazil, it arose from Typica

Pacas is a bourbon mutant from El Salvador. It was found in the mid/late (?)40's and it was selected because it was a much more compact plant that seemed to work well on the higher ridges where wind made standard bourbon a bit harder to grow.

Pacas and Maragogype were crossed to form Pacamara in the late 1950's in El Salvador.

Then you get into things like Catimor, Icatu and a number of other varieties that were developed by the forced (or natural) introduction of Robusta genetics. Robusta is bred in for disease resistance, root structure and obviously creates some cup-related issues/controversies.

Through selection we can isolate particular features that make a particular plant appealing (growth patterns, cherry color etc) and attempt to reproduce the results of a single plant. Since arabica is predominately self-pollinating, it takes a freak act of nature or intensive human intervention to change the genetics of the seed a plant produces.

If we find something we like in the field, we can generally assume the seeds from that plant will produce a plant of very similar features. If you want an exact genetic replica you can use tissue culture to clone the plant. This is time consuming and comparatively expensive, however you can see large-scale tissue culture projects in places like El Salvador. Generally these are run by NGO-funded research groups at a national level. You won't encounter tissue culture programs on your average farm, though I wouldn't be surprised if a handful of agronomist/farmers haven't taken this up as a hobby.

this recent message from El Injerto was very helpful in understanding this topic:

There are three different ways Coffee Arabica can pollinate:

-- Self-pollination: 91 to 93 percent of this specie pollinates naturally.-- Cross-pollination: 7 to 9 percent pollinates naturally, with the help of bees. New varieties are created.-- Artificial-pollination: with the help of men resulting in new varieties.

The main factors that contribute to an effective pollination are:

1. The species and the variety cultivated: particularly the age of the eggs of the plant.2. Temperature.3. Rain. It could wash the eggs remaining in the stigmas.4. Capacity of stigmas to capture pollen.5. Nutritional status of the plant.6. Growing regulators.

If you visit El Injerto at the end of the dry season, you will notice all coffee plants are covered with beautiful white flowers with five or six petals, very similar to jasmine. After pollination is over, flowers become fruits within two or three months. After six or eight months, cherries will be ready to harvest.

As you can see, nature is in charge of pretty much everything. The three basic ingredients for you to enjoy a great cup of coffee are:

1. The physical environment: the micro climate, type of soil, altitude… The “ideal conditions” for growing coffee.2. The plant and its natural input: we can´t create plants, but we can select the specie and the proper varieties for the physical environment we plant in.3. Our knowledge and experience in managing the plant in the field, the wet and dry process.

El Injerto's commitment is to maximize these three ingredients and our experience to produce the best quality coffee. El Injerto's quality approach is to delight you with a unique sensorial experience.

though I wouldn't be surprised if a handful of agronomist/farmers haven't taken this up as a hobby.

About 15 years ago I was on a very large conilon farm in Bahia where they were doing a lot of cloning. The yields per hectare they were getting were insane, and the farm consistently produced roughly 100,000 bags per year.